mirror of
https://github.com/justinian/jsix.git
synced 2025-12-10 08:24:32 -08:00
1308864061
- Moved MSR code to separate files with an enum class - Implemented syscall_enable in C++ using new MSR calls
86 lines
1.8 KiB
C++
86 lines
1.8 KiB
C++
#include "console.h"
|
|
#include "cpu.h"
|
|
#include "debug.h"
|
|
#include "msr.h"
|
|
#include "scheduler.h"
|
|
#include "syscall.h"
|
|
|
|
extern "C" {
|
|
void _halt();
|
|
void syscall_handler_prelude();
|
|
}
|
|
|
|
void
|
|
syscall_enable()
|
|
{
|
|
// IA32_EFER - set bit 0, syscall enable
|
|
uint64_t efer = rdmsr(msr::ia32_efer);
|
|
wrmsr(msr::ia32_efer, efer|1);
|
|
|
|
// IA32_STAR - high 32 bits contain k+u CS
|
|
// Kernel CS: GDT[1] ring 0 bits[47:32]
|
|
// User CS: GDT[3] ring 3 bits[63:48]
|
|
uint64_t star =
|
|
(((1ull << 3) | 0) << 32) |
|
|
(((3ull << 3) | 3) << 48);
|
|
wrmsr(msr::ia32_star, star);
|
|
|
|
// IA32_LSTAR - RIP for syscall
|
|
wrmsr(msr::ia32_lstar,
|
|
reinterpret_cast<addr_t>(&syscall_handler_prelude));
|
|
|
|
// IA32_FMASK - FLAGS mask inside syscall
|
|
wrmsr(msr::ia32_fmask, 0x200);
|
|
}
|
|
|
|
addr_t
|
|
syscall_dispatch(addr_t return_rsp, const cpu_state ®s)
|
|
{
|
|
console *cons = console::get();
|
|
syscall call = static_cast<syscall>(regs.rax);
|
|
|
|
switch (call) {
|
|
case syscall::noop:
|
|
break;
|
|
|
|
case syscall::debug:
|
|
cons->set_color(11);
|
|
cons->printf("\nReceived DEBUG syscall\n");
|
|
cons->set_color();
|
|
print_regs(regs);
|
|
break;
|
|
|
|
case syscall::message:
|
|
cons->set_color(11);
|
|
cons->printf("\nReceived MESSAGE syscall\n");
|
|
cons->set_color();
|
|
break;
|
|
|
|
case syscall::pause:
|
|
{
|
|
cons->set_color(11);
|
|
|
|
auto &s = scheduler::get();
|
|
auto *p = s.current();
|
|
p->flags -= process_flags::ready;
|
|
//log::debug(logs::task, "Pausing process %d, flags: %08x", p->pid, p->flags);
|
|
cons->printf("\nReceived PAUSE syscall\n");
|
|
return_rsp = s.tick(return_rsp);
|
|
//log::debug(logs::task, "Switching to stack %016lx", return_rsp);
|
|
cons->printf("\nDONE WITH PAUSE syscall\n");
|
|
cons->set_color();
|
|
}
|
|
break;
|
|
|
|
default:
|
|
cons->set_color(9);
|
|
cons->printf("\nReceived unknown syscall: %02x\n", call);
|
|
cons->set_color();
|
|
_halt();
|
|
break;
|
|
}
|
|
|
|
return return_rsp;
|
|
}
|
|
|